Pagoda cup coral reproducing?

rps20160112_180228_461.jpg
Did my pagoda cup coral reproduce or is this some kind of encrusting sponge or something? Curious because it and my cup coral are the exact same color and it's starting to develop little bubbles that look like mouths. I'd don't have this color encrusting going on any where else in my 60 gallon tank but on this rock.
 
View attachment 1988Did my pagoda cup coral reproduce or is this some kind of encrusting sponge or something? Curious because it and my cup coral are the exact same color and it's starting to develop little bubbles that look like mouths. I'd don't have this color encrusting going on any where else in my 60 gallon tank but on this rock.
Bottom left is the sponge thingy forming on the side of the rock where my pagoda sits
 
Top